BACKGROUND Studies involving superficial facial fat compartments are few in number with conflicting results. Most of them involved small study groups and compared measurements between different populations of young and old subjects either on cadavers or living subjects. OBJECTIVE To clarify volumetric and dimensional changes in midfacial superficial fat compartment retrospectively in patients who underwent a repeat magnetic resonance imaging (MRI) without gross pathology. MATERIALS AND METHODS A total of 70 patients with a mean age of 60 years (range: 33–82 years) and a median elapsed time of 44.5 months (range: 32–64 months) between 2 MRIs were included. Magnetic resonance imaging scans were analyzed in the axial and sagittal planes to obtain measurements of the medial part of the superficial cheek fat. Superficial cheek fat was divided into 3 compartments. Thickness, width, and height were measured, and volumes were calculated for each compartment on both hemifaces. RESULTS Volume and thickness were decreased significantly in all compartments (p < .05). The width was decreased in superior and middle compartments, whereas increased in lower compartment indicating dislocation of the fat tissue (p < .05). Height was also significantly increased (p < .05). A subgroup analysis has shown that there was no significant difference between men and women. CONCLUSION This study clarifies that aging is associated with a significant decrease in superficial midfacial fat tissue volume and thickness both in women and men. The decrease in width in upper and middle compartments, but increase in lower compartment suggests a volume shift within superficial fat tissue.

We aimed to obtain typical values for head, neck, chest, and abdominal computed tomography (CT) examinations from routine patients in 2018, and to review our data with national and international diagnostic reference levels (DRLs). METHODSSingle-phase head, neck, chest, and abdominal CT scans of adults performed in 64-slice CT in 2018 were included in this study. Radiation dose parameters of CT scans were obtained from the picture archiving and communication system of our hospital. Volumetric CT dose index (CTDI vol ) and dose length product (DLP) values were recorded. Effective dose (ED) and scan length was calculated. A 16 cm diameter phantom is referenced for head CT, and 32 cm diameter phantom is referenced for neck, chest, and abdominal CT. Descriptive statistics of the variables were given according to the normality testing. RESULTSMedian CTDI vol value was 53 mGy for the head, 13.1 mGy for the neck, 8.3 mGy for the chest, and 8.6 mGy for the abdomen. Median DLP value was 988 mGy.cm for the head, 299 mGy.cm for the neck, 314 mGy.cm for the chest, and 457 mGy.cm for the abdomen. Median ED value was 2.07 mSv for the head, 1.76 mSv for the neck, 4.4 mSv for the chest, and 6.8 mSv for the abdomen. Considering national DRLs, median CTDI vol values of head, chest, and abdomen were lower, whereas median DLP and ED values of head and chest were higher. For the abdomen, the median DLP and ED values were lower. CONCLUSIONOverall radiation dose parameters obtained in this study points out the need for optimization of head CT examinations in our institution.

Background Previous studies on alterations in superficial fat compartments with age yielded contradictory results; the superficial fat tissue volume or thickness was reported to increase, decrease, or remain unchanged. Aims To investigate volumetric and dimensional changes in superficial midfacial fat tissue retrospectively in patients who underwent a repeated computed tomography (CT). Methods A total of 262 patients (mean age, 46 years; median elapsed time between two CT imagings, 56 months) were included. Axial and sagittal planes were used for measurements of the medial part of the superficial cheek fat (SCF), which is divided into three compartments. The thickness, width, and height of each compartment were measured, and volumes were calculated for both hemifaces. Additionally, results were compared between males and females, and between three age groups: <45, 45–54, and ≥55 years. Results The total volume of SCF and inferior compartment was significantly increased compared with the first CT findings (p < 0.05). Upper and middle compartment volumes were found to decrease with age (p < 0.05). Thickness was decreased in the upper and middle compartments but not in the lower compartment. The width of the lower and middle compartments increased (p < 0.05), while the upper compartment did not show a significant change with age (p > 0.05). The height of the superficial fat layer was significantly increased at follow‐up (p < 0.05). The results were similar for both sexes and all age groups (p > 0.05). Conclusions SCF undergoes significant volume and dimensional changes with aging. Therefore, superficial fat tissue should be considered for enhancement of cosmetic treatments.

Objective: To investigate the feasibility of low dose chest CT acquisition protocol for the imaging of either the confirmed case of COVID-19 disease or the suspected case of this disease in adults. Method: In this retrospective case-control study, the study group consisted of 141 patients who were imaged with low dose chest CT acquisition protocol. The control group consisted of 92 patients who were imaged with the standard protocol. Anteroposterior and lateral diameters of chest, effective diameter and scan length, qualitative and quantitative noise levels, volumetric CT dose index (CTDIvol), dose length product (DLP), and size-specific dose estimations were compared between groups. Results: Radiation dose reduction by nearly 90% (CTDIvol and DLP values 1.06 mGy and 40.3 mGy.cm vs. 8.07 mGy and 330 mGy.cm, p < 0.001, respectively) was achieved with the use of low dose acquisition chest CT protocol. Despite higher image noise with low dose acquisition protocol, no significant effect on diagnostic confidence was encountered. Cardiac and diaphragm movement-related artifacts were similar in both groups (p = 0.275). Interobserver agreement was very good in terms of diagnostic confidence assessment. Conclusion: For the imaging of either the confirmed case of COVID-19 related pneumonia or the suspected case of this disease in adults, low dose chest CT acquisition protocol provides remarkable radiation dose reduction without adversely affecting image quality and diagnostic confidence.